A newborn camel and its mother are seen at the zoo in Zurich, Switzerland, on Thursday. Steffen Schmidt/Keystone/AP
Four charity runners dressed as knights chase a fifth runner dressed as Lady Guinevere as they pose for photographers near Tower Bridge in London on Thursday. The group will be competing, in costume, in the London Marathon on Sunday. Tom Hevezi/AP
A supporter of the ruling Sandinista National Liberation Front (FSLN) party does a back flip during a protest outside the National Assembly building in Managua, Nicaragua, on Thursday. Hundreds of Sandinista supporters demonstrated outside the Nicaraguan parliament, demanding that lawmakers approve social laws. Jorge Cabrera/Reuters
LSU's Gloria Johnson competes on the vault during the 2010 NCAA Gymnastics Championships in Gainesville, Fla., on Thursday. Phil Sandlin/AP
First Lady Michelle Obama walks the family dog, Bo, during an event to welcome children of Executive Office employees at the White House's annual Take Your Child to Work Day on Thursday. Evan Vucci/AP
Wilderness guide Stuart Wilde (r.) of New Mexico, leads a llama named K-2 as Michael Carlin leads Raja down Sunset Boulevard in Los Angeles, Calif., in honor of Earth Day. The two men brought the llamas into the city to inspire people to park their cars, go for a walk, and lessen traffic. Nick Ut/AP
A man lies on the grass on a sunny day at Lafayette Park near the White House on Thursday. Jonathan Ernst/Reuters
Thai soldiers take up position following several small explosions in the business district of Bangkok on April 22. Sukree Sukplang/Reuters
Tibetan monks attend a mass prayer for earthquake victims in China's Qinghai Province on Thursday. The official death toll from the magnitude-6.9 quake that shook a remote, mountainous corner of Qinghai Province last Wednesday has reached 2,183, with 84 people still missing, Xinhua news agency said. Kevin Zhao/Reuters
Britain's Liberal Democrat leader Nick Clegg listens to members of the Infant, Mother, and Pre-School Group at the Community Church in Greenway, England, on Thursday. The Liberal Democrats have doubled their projected vote share in Labour-held marginal constituencies, but the swing comes mainly from voters who were previously not sure they would vote, a poll showed. Gareth Fuller/Reuters
A Kenyan artist paints antipirate graffiti on a wooden board in the Kibera slum in Kenya's capital, Nairobi, on Thursday. Noor Khamis/Reuters
A Bornean flat-headed frog, which has the rare characteristic of being an amphibian without lungs and instead breathes entirely through its skin, is one of the recent discoveries in Borneo. A lungless frog, a frog that flies, and a slug that shoots love darts, are among the 123 new species discovered in Borneo since 2007, the result of a three-nation project backed by the WWF to conserve one of the oldest rain forests in the world. David Bickford/World Wildlife Fund/AP
A dog stands in thick, wet volcanic ash that covers the front steps of the Onundarhorn dairy farm in Hvolsvollur, Iceland, on April 22. Carolyn Kaster/AP
Staff and volunteers from the Turtle Hospital watch a 200-pound male loggerhead turtle, Pal, make its way to deeper water off the Florida Keys on Thursday in Marathon, Fla. The turtle was released on Earth Day after being treated for more than a month for an impacted digestive system. Andy Newman/Florida Keys Bureau/AP
Iran and five world powers agreed last week to extend by four months a deadline for reaching a final deal aimed at preventing Iran from acquiring a nuclear bomb. But a yawning gulf still has to be bridged.
Though diplomats from Iran and six world powers are talking up the “substantial progress” that led to an extension of nuclear talks until November, crucial differences still threaten a final deal to ensure Iran can never produce a bomb.